Re: I have set Aquamail as standart Email app.
Where?
Re: When I click on an Email link in the browser (Google Chrome Dev) the phone asks me to set up Email
The built-in Email app?
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I believe that standard Android doesn't have a "default email app" - only "browser, phone, sms", I checked a Nexus 5 with 6.0 and a Nexus 5x with 8.1 (8.1 has additional "home" and "pay" apps).
My old Huawei (with Android 7.0) does (have a setting for default Email app).
Hence - this is a Huawei specific enhancement and sounds like it doesn't work right.
What I'd do is go into phone Settings -> Apps -> three dots -> reset defaults.
Then next time you tap an email type link - you should be prompted with a choice between Email, Aqua Mail, maybe Gmail, and you'll be able to choose one as the default.
This is the "stock" Android mechanism, not the Huawei specific enhancement.